Interturbine ducts (ITD) are used for channelling hot combustion gases from a high pressure turbine stage to a low pressure turbine stage. The ITD is typically integrally cast with the stator vane set of the low pressure turbine stage. Lug and slot arrangements are typically used to connect the inner annular wall of the cast ITD to an inner baffle protecting the rear facing side of the high pressure turbine rotor. A separate annular seal is provided between the baffle and a rearwardly extending portion of the high pressure turbine rotor in order to seal the inter-stage cavity.
Although various baffle sealing arrangement have been proposed in the past, there is still a continuing need for a simpler baffle sealing arrangement.